can't compile with "error TS2304: Cannot find name 'AsyncGenerator'" (or 'AsyncIterable')

[bananaumai]

Hi, I'm really new to msgpack-javasript. I'm appreciated your great works first 😄

I'm facing errors saying like "error TS2304: Cannot find name 'AsyncGenerator'" when I compile my ts code with tsc.

My environment is something like below.

package.json

{
  "name": "msgpack",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@msgpack/msgpack": "^2.1.0",
    "typescript": "^4.0.3"
  }
}

tsconfig.jso

{
    "compilerOptions": {
        "moduleResolution": "node",
        "lib": ["ES2018", "DOM"]
    }
}

index.ts

import { encode } from "@msgpack/msgpack";

const encoded: Uint8Array = encode({ foo: "bar" });
console.log(encoded);

The following is the full error messages:

$ npx tsc index.ts
node_modules/@msgpack/msgpack/dist/decodeAsync.d.ts:5:162 - error TS2304: Cannot find name 'AsyncGenerator'.

5 export declare function decodeArrayStream<ContextType>(streamLike: ReadableStreamLike<ArrayLike<number>>, options?: DecodeOptions<SplitUndefined<ContextType>>): AsyncGenerator<unknown, void, unknown>;
                                                                                                                                                                   ~~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/decodeAsync.d.ts:6:157 - error TS2304: Cannot find name 'AsyncGenerator'.

6 export declare function decodeStream<ContextType>(streamLike: ReadableStreamLike<ArrayLike<number>>, options?: DecodeOptions<SplitUndefined<ContextType>>): AsyncGenerator<unknown, void, unknown>;
                                                                                                                                                              ~~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/Decoder.d.ts:27:25 - error TS2304: Cannot find name 'AsyncIterable'.

27     decodeAsync(stream: AsyncIterable<ArrayLike<number>>): Promise<unknown>;
                           ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/Decoder.d.ts:28:31 - error TS2304: Cannot find name 'AsyncIterable'.

28     decodeArrayStream(stream: AsyncIterable<ArrayLike<number>>): AsyncGenerator<unknown, void, unknown>;
                                 ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/Decoder.d.ts:28:66 - error TS2304: Cannot find name 'AsyncGenerator'.

28     decodeArrayStream(stream: AsyncIterable<ArrayLike<number>>): AsyncGenerator<unknown, void, unknown>;
                                                                    ~~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/Decoder.d.ts:29:26 - error TS2304: Cannot find name 'AsyncIterable'.

29     decodeStream(stream: AsyncIterable<ArrayLike<number>>): AsyncGenerator<unknown, void, unknown>;
                            ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/Decoder.d.ts:29:61 - error TS2304: Cannot find name 'AsyncGenerator'.

29     decodeStream(stream: AsyncIterable<ArrayLike<number>>): AsyncGenerator<unknown, void, unknown>;
                                                               ~~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/utils/stream.d.ts:1:45 - error TS2304: Cannot find name 'AsyncIterable'.

1 export declare type ReadableStreamLike<T> = AsyncIterable<T> | ReadableStream<T>;
                                              ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/utils/stream.d.ts:2:86 - error TS2304: Cannot find name 'AsyncIterable'.

2 export declare function isAsyncIterable<T>(object: ReadableStreamLike<T>): object is AsyncIterable<T>;
                                                                                       ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/utils/stream.d.ts:3:80 - error TS2304: Cannot find name 'AsyncIterable'.

3 export declare function asyncIterableFromStream<T>(stream: ReadableStream<T>): AsyncIterable<T>;
                                                                                 ~~~~~~~~~~~~~

node_modules/@msgpack/msgpack/dist/utils/stream.d.ts:4:83 - error TS2304: Cannot find name 'AsyncIterable'.

4 export declare function ensureAsyncIterabe<T>(streamLike: ReadableStreamLike<T>): AsyncIterable<T>;
                                                                                    ~~~~~~~~~~~~~

It would be appreciated if you give me any advise. Thanks.

[mcclure]

I am not connected with the msgpack-javascript project, I am a user. I cannot reproduce your error but I think that is because I am using Web instead of node.

According to several github issues on other projects, the solution is to add "es2018.asynciterable" to your lib array in tsconfig.json. Does that help?

If that fixes the problem, maybe msgpack should document this issue somehow.

[bananaumai]

@mcclure Thank you for your advice.

I tried as you suggested:

 {
     "compilerOptions": {
         "moduleResolution": "node",
-        "lib": ["ES2018", "DOM"]
+        "lib": ["ES2018.AsyncIterable", "ES2018.AsyncGenerator", "DOM"]
     }
 }

But, it didn't work for me, unfortunately. Thanks anyway!

[gfx]

Can you try "lib": ["es2020"]? This is used in

msgpack-javascript/tsconfig.json

Line 6 in 3794182

"lib": ["es2020", "dom"], /* Specify library files to be included in the compilation. */

[bananaumai]

@gfx Thanks for following up. I also try that way. But, again, it didn't work...

I'll give this issue some more investigation later.

[bananaumai]

Uh-oh,,,,, it was just the issue of the way to compile...

npx tsc --build tsconfig.json completely has worked.

This issue was just due to my lack of understanding on tsc.

I'm sorry and thanks again for your help @gfx , @mcclure .

[gfx]

Excellent!

Anyway, I've mentioned to prerequisites about TypeScript in README.md: 6d2c4bc

[bananaumai]

I've seen your commit, that must be really helpful. Thanks.